Tractor



4 Sheets-Sheet 1 ay 15, l923.

F. HODGKISS TRACTOR Filed May 1o, 1921 "e Il!! I A n I r hr :All IIIIOIIAI I/ -0.-- Il |l| l d u t a F. HODGKISS TRACTOR Filed May l 10 1921 4 Sheets-Sheet 2 N @WKN INVENTOR. FIM wr l/aaG/r/ss ATToRNE l.9.

May 15, 1923.

F. HODGKSS TRACTOR Filed May 10, 1921 4 Sheets-Sheet 5 ffm/wf Haas/wss 1f 'ENTORA .-1 TTORNEYS,

Patented ay 15, 1923.

FRANK HODGKISS, OF OAKLAND, CALIFORNIAn TRACTOR.

Application filed May 10, 1821. ,Serial No. 468,338.

To all whom t may concern:

Be it known that I, FRANK HooGKIss, a citizen of the United States, and resident of Oakland, county of Alameda, and State of California, have invented a new and useful Tractor, of which the following is a specification. f

The present invention relates to improvements in track-laying tractors, and its principal object is to provide a tractor of the track-laying type that will be very compact in its shape, and in which clutch, transmission and differential are combined in a simple, compact working unit, allowing both sides of the tractor to be worked as separate, independent parts. A furthercobject is to provide a tractor which has the draw bar attachment forward of its center whereby the pulling capacity as compared with the power and size of the machine is increased considerably. Another object is to provide means giving strong lateral support to the track-laying mechanism in case the tractor goes over uneven ground causin one side to be higher than the other.

attain these objects by means of the mechanism illustrated in the accompanying drawing, in which Figure 1 shows a side view of my tractor; Figure 2 a plan view of the same, with the motor removed; Figure 3 a front view of the same with the motor and fly wheel removed; Figure 4 a detail view illustrating the reverse gear mechanism; Figure 5 a detail view showing the draw bar attachment; Figure 6 a perspective view of a gear shifting link, and Figure 7 an enlarged detail view of a clutch lever used in my transmission.

Referring to the drawings in detail, the tractor (1) is supported on two endless tracks (2) each of which is adapted to travel on or around a track frame (3), two idlers (4) and (6) and a sprocket wheel (7) adapted to transmit motion to the track from its shaft (8). The particulars of this endless track are described in the co-pending divisional application Serial No. 523,- 972, which is hereby referred to.

The shaft (8) is supported in a bearing (11) resting on the track frame and forms the support for the rear end of the main frame The shaft (8) does not extend from one side of the tractor to the other, but i-s broken in the center, as shown at (14) so that each half of the shaft is adapted to rotate independently of the other half.

, supported The front art of the main frame (13) is Ey the sprin s (16) resting at either end on the shaft or the idler (6).

The frame supports the motor and the transmission. The motor may be of any type adapted to do the work required of it and does not need any further description in this connection. The crank shaft (17) run by the motor is supported rearwardly of the motor by the plate (18) stretched across the frame in transverse direction and carries at its rear end the bevel gear (19) which latter is adapted to engage and rotate the cogs in the beveled ange (21) of the drum (22), which encloses a multiple disk clutch mechanism well known in the art and' therefore not described in detail. This clutch mechanism is adapted to transmit the rotary motion of the drum (22) to either end of the main shaft (23) when enn gaged by either spring (24). The mechanism is thrown out of clutch against the resistance of the springs (24) by the foot levers (26) one of which is shown in detail in Fi ure 7 and comprises a longitudinal rod 27) pivotally secured in the rear of the frame and the plate (18) and a transverse rod (30) secured to its rear end and running parallel to the rear frame member. rlhe transverse rod has a foot pedal at its far end, Within convenient reach of the driver, who can, by stepping on this foot pedal, impart rocking motion to the longitudinal rod (27) and its downwardly extending fork (28) which engages a groove (29) in the sleeve (31) slidably secured to the shaft (23) and thereby forces the shaft outward against the resistance of the spring (24) so as to release the clutch.

rlhe sleeve (31) carries two gears (32) and (33), the former being closer to the clutch and of larger diameter than the other. These two gears are adapted to be engaged by two gears (34) and (36) rigidly secured to the sleeve (37), which latter is adapted to slide on the jack shaft (8) carrying the sprocket wheel (7). When in neutral, this sleeve is positioned between the two gears on the main shaft so that none of the gears mesh. When the sleeve is pushed toward the outside of the tractor, its outer and larger wheel (36) meshes with the gear (33) on the shaft (23), thereby engaging the slow speed of the tractor. Pushing the sleeve (37) inward will similarly mesh the gear (34) with the gear (32), thereby 'engaging the second speed. The sleeve is controlled by the lever (38), (see Figure 1,) which pivots in a projection (39) of the rear member of the main frame and the lower end of which engages the horizontal fork at the rear end of a link (41) sliding on a shaft (42) supported in brackets (43) depending from the frame. The front end (40).of the link (41), being forked, vertically engages the sleeve (37) between its two gears and is adapted to push the sleeve in the desired direction.

Attention is called to the fact that either side of the transmission represents a distinct, independent working unit and either side can be in clutch, out of clutch, in slow speed or in second speed or in neutral, without affecting the other side.

Each side also has an independent reverse mechanism, actuated by aseparate lever (44) for either side. The idler gear (46), which brings about the reverse motion, is adapted to rotate on a concentric wheel (47), (see Figure 1,) which latter is eccentric-ally and pivotally supported on the pin (48) resting in brackets (51) secured to the main frame and the cross-member (18). The lever (44) is also secured to said eccentric pin and has a second eccentric support (52) on the wheel (47), by means of which it is enabled to rotate the wheel on the eccentric pin and thereby to change the axial position of the reverse gear. The latter is preferabl in constant mesh with the gear (36) an is wide enough to overlap the gear (33) on the main shaft so as to enga-ge the same when the wheel (47) is shifted on its eccentric pin. The reverse gear can be used only when the forward speeds are in neutral, that is when the relative position of the different gears is as shown in Figure 2, and it will be readily seen that in this case a rearward thrust of the lever (44) will throw the reverse gear in mesh with gear (33), thereby causing the gear (36) to rotate in the same direction as gear (33) and reversing the direction of its respective side of the tractor. It is understood, of course, that the reverse can be handled separately and independently for v each side of the tractor so that each side re resents a complete working unit and can worked by itself. This is of particular import-ance since the steering of the tractor is done exclusively by the varying speeds of the respect-ive sides. and my mechanism allows of the greatest latitude in this respect. Assuming` for instance, that the machine travels at second speed and it is desired to turn tothe right, the operator can accomplish this by either setting his right hand gear inslow speed orl in neutral or in reverse, according to the sharpness of the turn desired.

A special feature of my tractor is its draw bar attachment which is secured to the frame near its center. In consists of a heavy plate (53) secured to the main frame and but bears against the brace and thereby steadies the tractor when the same is travelling on uneven ground so that one side is higher than the other.

The draw bar (56) is attached to the center of said plate as shown at (57 and eX- tends from there rearwardly so as to pass through a slot (58) in bracket (59) extending downwardly from the rear member of the main frame.

I claim: ,l

1. In a tractor, a transmission comprising a longitudinal shaft driven by the motor, a transversely disposed clutch adapted to be rotated by said shaft, a transverse shaft mounted co-axially with the clutch having transmission gea'rs thereon, a longitudinal rod terminating in a transverse rod rearwardly of the clutch with a foot pedal at its free end, and a fork in the longitudinal rod engaging the transmission gears causing the same to be engaged with the clutch when the foot pedal is actuated.

2. In a tractor, a frame, a longitudinal drive shaft mounted therein, a transversely disposed clutch drum adapted to be rotated by the drive shaft, a transverse shaft mounted co-axially with the drum having transmission gears thereon, a longitudinal rod terminating in a transverse rod rearwardly of the rear frame member with a foot pedal at its free end, and a fork in the longitudinal rod engaging the gears causing the gears to be engaged with the clutch when the foot pedal is actuated.

3. In a tractor, a transmission comprising a longitudinal shaft driven by the motor, a

4transversely disposed clutch adapted to be rotated by said shaft, two transverse shafts mounted co-axially with the clutch, each having transmission gears thereon, two longitudinal rods terminating in transverse rods running alongside one another rearwardly of the clutch with foot pedals at their free ends, and a fork in each longitudinal rod engaging one of the transmission gears causing the same to be4 engaged with the clutch when its foot pedal is actuated.

4. In a transmission for tractorsa longitudinal shaft, a -transverse sha-ft', a clutch coaxially mounted on the transverse shaft, a gear coaXially fixed to one part of the clutch, a driving pinion on the longitudinal shaft in constant driving relation with said gear, high and low speed gears coaxially mounted in spaced relation on the transverse shaft on' each side of the clutch, a jack shaft positioned parallel of the transverse shaft below and to one side of the same, a plurality of gears coaxially mounted on the jack shaft corresponding ears on the jack shaft for corresponding to the high and low speed reversing the rive, and means for selec- 10 gears on the transverse shaft, means for tively actuating the idler gears to enga sliding the gears on the jack shaft into and the low speed gears on the transverse sha s out of mesh with the high and 10W speed all of said gears including the clutch being gea'rs to change speed, an idler gear mounted positioned with their axes pa'rallel to one adjacent each of the low speed gears and another. adapted to function between them and the FRANK HO'DGKISS.' 

